Communications switching devices find use in applications in which the capability is desired for the selective coupling of one of two or more devices, such as a processor or controller, to a third device, such as a modem or a business terminal, for example. The modem or terminal can thus be shared between the devices, in accordance with changing requirements.
A need exists for such a switching device which enables the selection of one of the first or second devices to be made from that side of the switch and which resolves contention when more than one of the first and second devices desire to establish a connection with the third device at the same time.